I'm planning to go back to California and Nevada next year in March and this time I'd like to include a visit to one of the national parks, especially Bryce or Zion Canyon, when I'm in Las Vegas. But I can't drive. Could you recommend a good tour company that could organise day trips there? The few I've found on the net only seem to offer tacky, cowboy-style excursions. Also, is the weather going to be acceptable at that time? Laurent de Alberti, Highbury

Las Vegas has a massive range of tours to surrounding attractions - you can head off white water rafting, 4x4 off-roading, hiking in the Grand Canyon or take helicopter flights over the Hoover Dam and still be back on the Sunset Strip for an evening at the roulette wheel. Vegas operates as a year-round destination, so going in March you should have no trouble picking something up. However, Bryce Canyon and Zion are a long way from Vegas, and for three hours in Bryce Canyon you're looking at a 13 to 15-hour day; Zion is slightly nearer. You'll have no trouble finding something once you get out there, but try www.vegasguide.com for details of a one-day coach tour, which should cost between £140 and £160 including lunch and bottled water. Missing Link Tours (00 1 702 453 7193) offers a two-day hiking tour of both national parks for around £140.

In March, Vegas has an average high of 22C, but things will get much colder as you get to Zion and Bryce Canyon. Expect some snow around, though roads are ploughed and should remain open. The Easter weekend is very busy - book ahead.

Visiting Mexico's ruins

My eldest son will be studying in Guadalajara, Mexico, during the next academic year and I plan to visit him with my younger son, daughter and her boyfriend over Christmas. We would like to include trips to Mayan and Aztec sites (though the Yucatan is too far) as well as organise some windsurfing. Is this possible by public transport or should we hire a vehicle - I've heard such horror stories about driving in Mexico. Davina Hitchcock, by email

Mexico has an excellent public transport network, with frequent and often very comfortable buses to almost all the ancient sites. Places you shouldn't miss include Teotihuacan's huge pyramids, El Tajin's jungle-ringed ruins, Tula's huge warrior figures and the well-preserved frescoes at Cacaxtla. While these aren't day trips from Guadalajara, you could spend a few days touring round - accommodation is plentiful and inexpensive.

For Mayan sites such as Chichen Itza and Uxmal, you will have to venture further south - but you could consider a flight to Cancun from Guadalajara (normally via Mexico City) which would give you access to the Yucatan's many amazing attractions. Fares vary greatly depending on when you fly, and a variety of passes are available - Aeromexico (020 7801 6234) and Mexicana (020 8492 0000) can provide further information.

Driving in Mexico can be convenient if time is short, but you should be aware that road conditions are not even close to European or North American standards. On mountain roads there are often steep drops into the valley, which can be daunting if you're not experienced in this type of driving. Hire generally starts at around £30 for a small car. Make sure you're fully insured.

You can windsurf at any of Mexico's many coastal resorts - try Puerto Vallarta and Manzanillo, both a few hours from Guadalajara. Contact the Mexico Tourist Board (09065 508 917) for brochures, or visit www.mexico-travel.com for more about the country.

Leech-proof socks

Any idea where I can purchase leech-proof socks? I've been advised to wear them while trampling through the jungle in Borneo. Roy Scattergood, by email

Where there's rainforest, there's a chance you may run into leeches - or rather, they may run into you. Normally maggot-sized, leeches burrow through your socks to suck on your ankles (or anywhere else they can reach). Leech-proof socks, which go under your regular socks, are available from Nomad Travel (020 8889 7014). Other potential ways to combat leeches include wearing gaiters. You could try wearing two pairs of socks, soaking the top sock in very salty water and then drying it before putting it on.

If you do find yourself getting attached, don't pull the leech off, as it may leave behind mouthparts, which will make the wound more vulnerable to infection. Tried and tested methods of removing leeches include applying salt to the leech, or touching it with a flame from a match or lit cigarette.

A night at the opera

We would like to see some Italian opera in Italy as a birthday treat in December or January. La Scala, Milan, would be good, but have you any recommendations? Is it best to find a company that gives a two- or three-night package, or should we try to get tickets and accommodation ourselves? David Siddans, Wakefield

Getting tickets for La Scala yourself is all but impossible - tickets are snapped up within minutes of going on sale, requiring perseverance or luck to get hold of one. What is available can be booked at www.teatroallascala.org. Failing that, a package can be arranged with opera specialists Brompton Travel (020 8549 3334) but tickets will be very expensive. Tickets for high-class opera performances in Turin, Florence and Genoa can be easier to come by and cheaper than Milan, if you take a package. For example, when it's open, you can book direct with the box office of the Teatro Regio in Turin (00 39 011 88151). Travel towards the end of January to avoid the Christmas and New Year rush - both travelling and in the opera houses.

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